document.write( "Question 255021: A motor boat traveling at 18 miles per hour traveled the length of a lake in one-quarter of an hour less time than it took when traveling at 12 miles per hour. What was the length in miles of the lake? \n" ); document.write( "
Algebra.Com's Answer #187316 by stanbon(75887)\"\" \"About 
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A motor boat traveling at 18 miles per hour traveled the length of a lake in one-quarter of an hour less time than it took when traveling at 12 miles per hour. What was the length in miles of the lake?
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\n" ); document.write( "Let the length of the lake be x miles.
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\n" ); document.write( "Fast-trip DATA:
\n" ); document.write( "rate = 18 mph ; distance = x miles ; time = x/18 hr.
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\n" ); document.write( "Slower-trip DATA:
\n" ); document.write( "rate = 12 mph ; distance = x miles ; time = x/12 hr.
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\n" ); document.write( "Equation:
\n" ); document.write( "slow time - fast time = 1/4 hr
\n" ); document.write( "x/12 - x/18 = 1/4
\n" ); document.write( "Multiply thru by 36 to get:
\n" ); document.write( "3x - 2x = 9
\n" ); document.write( "x = 9 miles
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "
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